Electrical connector structure



May 24, 1966 P. E. HARRISON ETAL 3,253,250

ELECTRICAL CONNECTOR STRUCTURE Filed Nov. 26, 1963 5 Sheets-Sheet l NI IMI rroeA/Eys.

May 24, 1966 P. E. HARRISON ETAL. 3,253,250

ELECTRICAL CONNECTOR STRUCTURE 5 Sheets-Sheet 2 Filed NOV. 26, 1963 INVENTORS. Maz. E. HQQ/son/ Haeow COA/Lossv y fwn f M rraeA/Eys.

May 24, 1966 P. E. HARRISON ETAL 3,253,250

ELECTRICAL CONNECTOR STRUCTURE 5 Sheets-Sheet 5 INVENTORS.

Traa/Err Filed Nov. 26, 1963 United States Patent O 3 253,250 ELECTRICAL CONECTUR STRUCTURE Paul E. Harrison, Tustin, and Harold Comlossy, Whittier,

Calif., assignors, by mesne assignments, to International Telephone and Telegraph Corporation, New York,

N.Y., a corporation of Maryland Filed Nov. 26, 1963, Ser. No. 325,927 Claims. (Cl. 339-177) The present invention relates to the electrical connectors, and it relates particularly to an electrical connector having novel mating contact members wherein at least one of the contact members is subjected by its mating contact member during engagement therewith to a novel bending and `stressing action which results in an assurance of good contacting pressure in the mated position and provides a good wiping or cleaning action to remove surface impurities such as oxides on the contacts, all of which improves the electrical continuity between the contacts in their mated positions. Although the present invention is not limited to electrical connectors employed in any particular use or environment, it has particular utility where the connector is subjected to such adverse environments as extreme heat or a corrosive atmosphere or both, since these conditions frequently occur together.

The invention further relates to a novel supporting arrangement of the contact members in the connector members capable of maintaining a sealed condition in the connector members despite extreme temperature changes which would normally destroy a seal because of different thermal expansion coeilicients of various connector parts.

It has long been a problem in the electrical connector art to provide mating contact terminal members which would produce a reliable electrical connection despite adverse or widely varying environmental conditions. For example, contacting pressure is conventionally provided by employing one or both mating contacts which have spring characteristics, the spring or springs being exed to provide the contacting pressure during engagement of the contacts. However, under high temperature conditions, as for example 1800 F., Which are frequently encountered in thermocouple and power circuits, the spring characteristics are either seriously diminished or substantially lost, which causes a corresponding reduction or loss of electrical continuity between the contact members.

Oxidation and corrosion from adverse environmental conditions also present a serious problem in the art. For example, electrical connectors which must operate in a corrosive atmosphere or a highly oxidizing atmosphere will frequently have their mating contact terminal members corroded or oxidized so that the mating surfaces are relatively poor electrical conductors, and the electrical characteristics of the connector will be correspondingly diminished. An example of this type of situation is again where the connector must operate in an environment of elevated temperature, which is a condition that promotes oxidation of the contact terminal members.

Because of these and other problems in the art, it is an object of the present invention to prov-ide an electrical connector embodying mating contact' terminal members which are so constructed and arranged that at least one of them will, upon engagement of the contact members, be bent both transversely to the engaging axis and longitudinally along the engaging axis so as to provide a compound bending or flexing thereof which assures good contacting pressure and surface wiping or cleaning between the contacts.

Another object of the present invention is to provide an electrical connector of the general character described wherein one or more mating pairs of pin and socket contact members are provided, each pin contact member Patented May 24, 1966 ICC comprising one or more elongated resilient ribbons of conducting material which are arcuate or arch-shaped in cross-section, and each mating socket contact member comprising structure having a pair of spaced surfaces defining an elongated slot which is arcuate in cross-section but has a dilferent radius of curvature than the pin contact ribbon or ribbons, the socket slot being sufficiently narrow to produce -transverse deflection or bending of the pin contact ribbon or ribbons as they are inserted into the slot. In a form of the invention shown and particularly described herein, the socket slot is annular and the pin ribbons are portions of a longitudinally split tube having a smaller diameter than the socket slot.

A further object of the invention is to provide an electrical connector of the general character described wherein the longitudinal axis of the pin ribbons is transversely offset from the longitudinal axis of the mating contact socket, and entrance ramp means is provided for guiding the pin ribbons into the sockets, whereby when the pins are engaged in the sockets and the pin and socket contact members are moved toward the fully mated positions, the pins are deflected transversely in one direction as they enter the respective sockets and then are deflected back toward the longitudinal direction, thereby producing a longitudinal serpentine interference action between the pins and sockets in the mating positions. In the preferred form of the invention, this longitudinal serpentine interference fit is combined with the transverse arch or arcuate interference tit to provide the preferred compound interference t and wiping action of the present invention.

An additional object of the invention is to provide an electrical connector embodying a plurality of mating pairs of tubular pin and socket contact members of the character described which are disposed in a coaxial arrangement to produce a coaxial connector.

A still further object of the invention is to provide an electrical connector having contact members of the character described wherein rearward tubular portions of the contact members are attached to and interfitted with a plurality of tubular insulator members in such a manner as to provide hermetic seals in the connector members, which seals are expansible and contractable according to temperature changes.

Further objects and advantages of this invention will appear during the course of the following part of this specification, wherein the details of construction and mode of operation of a preferred embodiment are described with reference to the accompanying drawings, in which:

FIGURE l is an axial section, with portions in elevation, illustrating an electrical connector embodying the present invention and comprising a pair of connector members which are shown fully operatively engaged.

FIGURE 2 is an enlarged, fragmentary axial section, partly in elevation, illustrating the center pin and socket contacts of FIGURE 1, partly engaged and moving toward their fully mated position.

FIGURE 3 is an enlarged transverse section taken on the lines 3-3 of FIGURE 1.

FIGURE 4 is an axial section, partly in elevation, illustrating one yof the connector members, the receptacle member, of |FIGURE l.

FIGURIE 5 is an enlarged fragmentary transverse section taken on a line 5-5 in FIGUIRE 4, illustrating the socket contact vmembers in front end elevation.

FIGURE 6 -is an enlarged fragmentary transverse section taken on a line 6 6 in FIGURE 4.

FIGURE 7 is an -axial section, partly in elevation, showing the other vconnector member, the plug member, of FIGURE l.

FIGURE 8 is an enlarged transverse section taken on line 8 8 in FIGURE 7, showing `the pin contact members in end elevation.

FIGURE 9 is a perspective View of the outer pin contact sleeve portion of the plug connector member shown in FIGURE 7.

Referring to the drawings, the present invention has been illustrated in connection with a coaxial electrical connector comprising a receptacle connector member 12 and a plug connector member 14. The receptacle connector member l.12 is best shown in FIGURE 4, and the plug connector member |14 is best shown in FIG- URE 7. The receptacle andplug connector members l2 and 114, respectively, are illustrated in `their fully engaged relationship in [FIGURE 1.

Referring now particularly to FIGURES 4, 5 and 6, the receptacle connector member 12 will now be described in detail. Receptacle L12 includes a shell 16 having a generally cylindrical forward engaging portion 118 which is externally threaded so as to be threadedly en- -gaged with lthe plug 14 and which has an externally beveled forward lip `20. A polarizing key 22 is provided on .the inner wall ofthe forward portion 18 of shell 16.

Re-arwardly positioned on the receptacle shell 16 is yan external mounting flange 24, and extending rearwardly from -shell 16 is an end Abell 26 which may be brazed or Welded or otherwise secured and sealed to shell 16. A cable 28 'having an outer metal sheath extends into the end bell 26 through apertured rear end `29 of the end bell, the cable 28 including a pair of conductor wires 30 which are bared so as to project forwardly from the main body of the cable.

A metal sleeve 32 is welded about the forward end of the cable jacket within the end bell 26, and a ceramic cable end plug v34 is brazed within the portion of the metal sleeve 32 fwhich extends forwardly from the cable end. The wires 30 extend forwardly thro-ugh respective passages 35 .which extend longitudinally through Ithe end plug 34. i

The cable end is thermetically sealed within the end bell K26 by means of an annular brazing preform 36 which is 4radially positioned between the cable and the Wall of `the end bell rearwardly of the sleeve 3:2.

The mounting of the socket contact members within the receptacle shell 16 will now be described. An outer metal mounting sleeve 38 is disposed within the rearward portion of receptacle shell 16, and is secured to the inner wall of shell 16 proxima-te its rear end by an annular metal-to-ceramic braze 42. Coaxially disposed .within the mounting sleeve 38 is an outer ceramic insulator sleeve `40, rwhich may be composed of alumina or other suitable ceramic material. The ceramic sleeve 40 is bonded to the inner wall of mounting sleeve 38 at the forward portion of sleeve 38 by an annular metal-toceramic braze 44.

IMounted coaxially -within the outer ceramic insulator sleeve 40 is outer socket contact structure l46 which comprises two members, an outer contact sleeve 48 and an inner Contact sleeve 50. An axially extending .annular space 52 is deiined between outer and inner contact sleeves 48 and 50, respectively, for receiving the forward portion of the mating pin contact member. An annular rib 54 projects radially inwardly from the forward end of the outer c-ontact sleeve 48 and serves as a guide for proper radial positioning of the mating pin Contact mem- 'ber as it enters the socket. Rib 54 also assists in defining the abruptness of the longitudinal, serpentine bend applied to the mating pin contact member. The forward end of the inner cont-act sleeve 50 is spaced rearwardly from the rib 54 and is provided with an external entrance ramp or -bevel 56 for deflecting the forward end of the mating pin contact member radially outwardly and thence into the annular socket space 52.

The inner contact sleeve 50 is provided with -a stepped central portion 58 which is proximate the forward end of ceramic insulator sleeve 40 and with a rearward cylindrical portion 60 of substantially the same diameter as the outer contact -sleeve 48 and extending rearwardly adjacent to and generally coextensively with the cylindrical inner Wall of the insulator sleeve 40. The outer contact sleeve 48 is bonded at its rear end to the stepped central portion 58 of inner contact sleeve 50 by welding or brazing or -other suitab-le means, so that the outer and inner socket 4contact sleeves 48 and 50 serve as an integral -contact unit. A terminal tab 62 forms an integral part of the rearward portion 60 of contact sleeve 50 .and extends rearwardly therefrom into the cavity of end bell 26, one of the wires 30 being brazed or welded to the tab 62.

Coaxially disposed within the rearward cylindrical portion '60 and the stepped central portion 58 of inner contact sleeve 50 is an inner ceramic insulator sleeve 64 which is stepped down toward its forward end to a reduced diameter forward portion 66 which enters the forward cylindrical bore portion I67 of inner contact sleeve 50.

The inner cylindrical wall of outer ceramic insulator sleeve 40 is grooved proximate the rear end of sleeve 40 to receive an annular metal-to-ceramic braze 68 bonding the outer ceramic insulator sleeve 40 to the rearward cylindrical portion. 60 of inner contact sleeve 50. A clearance is provided between the stepped central portion 58 of inner contact sleeve 50 and the reduced diameter forward portion 66 of inner ceramic insulator sleeve 64 to receive .an annular braze 70 bonding the inner contact sleeve 50 with the inner ceramic insulator sleeve 64.

Coaxially disposed within the inner ceramic insulator sleeve 64 is central socket contact structure 72 comprising an outer contact sleeve 74 and an inner contact rod 76, the sleeve 74 .and rod 76 defining an axially extending annular space 78 therebetween for 4receiving the forward tubular end portion of a mating pin contact member.

The outer contact sleeve 74 has an annular, inwardly projecting rib 80 1at its forward end for `guiding the mating pin contact member into the socket contact structure 72. The forward end of inner contact rod 76 is spaced rearwardly from the rib 80 and is provided with an entrance ramp or bevel l82 for deflect-ing the mating pin contact member radially outward-ly and guiding it into the annular space 78.

The inner contact rod 76 has a stepped central portion 84 and extends rea-nwardly therefrom in a rearward cylindrical portion 86 which has 1a terminal tab 88 extending rearwardly therefrom into the cavity defined within end bell 26, the 'other ,wire 30 being welded or brazed to talby 88. The outer contact sleeve 74 of central contact structure 72 is welded, brazed or otherwise integrally secured to the stepped central portion 84 of inner contact rod 76 so that sleeve 74 and rod 76 together comprise a unitary contact structure.

The inner cylindrical wall of inner ceramic insulator sleeve 64 is recessed proximate the `rea-r end of inner insu-lator sleeve y64 for provision of an `annular metal-toceramic braze90 between the inner ceramic insulator sleeve 614 `and the rearward cylindrical portion 86 of the inner contact rod 76.

It will be noted from FIGURE 4 and (from the foregoing description that the annular 'metal-toJceramic brazes employed in the mounting of outer metal mounting sleeve 38, outer and inner ceramic insulator sleeves 40 and 64, respectively, -and outer and central socket contact structures 46 and 72, respectively, are staggered. Thus, sulbstantially the entire length of outer metal mounting sleeve` the coaxial parts except for the brazes, provides a bellowlike Ihermetically sealed construction wherein thermal expansion and contraction is permitted by a slight flexing of the various cylindrical metallic members, including the outer metal mounting sleeve 38, the cylindrical portion 60` of the outer socket contact structure 46, `and the rearward cylindrical portion 86 of the central socket contact structure 72.

The plug connector member 14 will now be described in detail Iwith reference to FIGURES 7, 8 and 9 of the drawings.

Plug connector ymember 14 includes a shell 92 :having a generally cylindrical `forward engaging portion 94 adapted for sliding engagement within the forward port-ion 18 of receptacle shell 16. The [forward engaging portion 94 of plug shell 92 includes a longitudinally arranged polarizing slot 96 adapted to receive the receptacle polarizing key 22.

Rotatably mounted on the plug shell 92 is an internally threaded coupling sleeve 98 adapted for threaded engagernent with the external threads on the receptacle shell :16. Coupling sleeve 98 is retained against axial shifting on the plug shell 92 by means of a positioning ring 100 on the plug shell to the rear of the coupling sleeve 98 and a deformable gasket 102 on the plug shell spaced forwardly from ring 100. The deformable gasket 102 is atiixed and sealed to the plug shell 9-2 by means of a wire rin-g brazing preform 104, land gasket 102 includes a forwardly `and outwardly ilaring lip portion 106, the outer surface of which bears against a beveled annular surface 108 of coupling sleeve 98. As best shown in -FIGURE 1, 'when the plug and receptacle connector members are inter-engaged, during the nal tightening rotation of coupling sleeve 98 about the externally threaded portion of receptacle shell 16, the outwardly flaring lip portion 106 of gasket 102 will form a coupling seal between the beveled annular surface 108 of the plug coupling sleeve 98 and the beveled forward lip 20 of the receptacle shell 16, the bevels l108 and 20 having substantially the same angle of incidence with respect to the longitudinal axis of the connector.

Referring again to FIGURES 7, 8 and 9, the plug connector member 14 has an end bell 110, a cable end \1|12 extending through the apertured rear end of end .bell 1'10. The end of cable 112 is stripped back to expose a pair of conductor wires 114 which extend into the forward portion of end bell 110. A -rnetal sleeve 1i16 is welded to the forward end portion of the cable jacket, projecting forwardly from the cable jacket to receive a ceramic cable end plug 118 which is brazed or otherwise atlixed Within sleeve `116, end plug 118 having a pair of longitudinal bores through which the Wire conductors 114 extend. A brazing preform l120 secures the cable 112 in the rear end portion of end bell 1,10 and provides a seal between the cable 112 and the end bell 110.

The construction and mounting yof the pin contact terminal members in the plug connector member 14 will now be described in detail with reference to FIGURES 7, 8 and 9.

An outer metal mounting sleeve 122 is coaxially disposed within the rearward portion of plug shell 92, and coaxially disposed within .mounting sleeve i122 is outer ceramic insulator sleeve 124 which may be made of alumina or other suitable ceramic material. The ceramic insulator sleeve '124 extends `from slightly forward of the rear end of plug shell 92 to a forward end which is disposed slightly to the rea-r of the forward end of plug shell 92. The forward end of ceramic insulator sleeve :124 is preferably internally chamfered or beveled to provide a lead-in yfor the outer socket contact structure 46.

Outer metal mounting sleeve i122 is secured in sealed relation to the plug shell 92 by means of an annular braze 126 between the outer cylindrical 'wall of sleeve l1212 at the inner cylindrical ywall of shell 92 proximate the rear ends of sleeve ,122 and shell 92. The ceramic insulator sleeve 124 is secured and sealed to mounting sleeve 122 by means of a metal-to-ceram-ic braze l128 annularly disposed -between the outer cylindrical surface of ceramic sleeve i124 and the inner cylindrical surface of metal mounting sleeve `1122 proximate the forward end of Imounting sleeve 122.

Coaxially disposed -within outer ceramic insulator sleeve 124 is outer pin contact structure 130 which is generally in the form of a sleeve. The pin contact structure 160 includes a generally tubular forwardly contacting portion 1132 having a plurality of regularly spaced longitudinal slits .134 therein which provide Ia plurality of elongated contacting lingers 136 'which are arcuate or arch-shaped in cross-section. The fingers 136 are preferably composed of metal having good spring characteristics. Although four slits 134 and ffour contacting fin-gers 136 are shown in the drawing, as best -illustrated in FIGURES 8 and 9, it is to be understood that any number of such slits 134 and contacting lingers 136 may be employed as desired within the scope of the invention.

T'he outer pin contact structure .130 includes a rearward cylindrical portion 138 of slightly larger diameter than the forward portion 132, the rearward cylindrical portion 138 terminating in a rearwardly extending ter-. minal tab '140 which projects into the cavity lof end bell and has one of the conductor wires 114 attached thereto as by brazing or Welding.

Coaxially disposed within the outer pin contact struc ture is inner ceramic insulator sleeve 142 having a reduced external diameter forward portion 144 which is generallylongitudinally coextensive with the reduced forward contacting port-ion 132 of the outer pin contacting structure 130.

The outer ceramic insulator sleeve 124 is undercut proximate its rear end to receive an annular braze 146 for securing the outer pin contact structure 130 in sealed relationship to ceramic insulator sleeve 124. An annulaiI space is provided between pin contact structure 130 and inner ceramic insulator sleeve 142 immediately to the rear of the forward contacting portion 132 of contact structure 130 to receive an annular braze 147 which secures and seals the inner ceramic insulator sleeve 142 to the outer pin contact structure 130.

A relatively large `annular clearance 148 is provided between the forward contacting portion 132 of pin contact structure 130 and the inner cylindrical wall of outer ceramic insulator sleeve 124 to receive the outer contact sleeve 48 of the mating outer socket contact structure 46, while a relatively narrow annular clearance 149 is provided between contacting portion 132 of outer pin contact structure 130 and the reduced diameter forward portion 144 of inner ceramic insulator sleeve 142 to receive the beveled entrance ramp 56 of the inner socket contacts sleeve 50 of the mating socket contact structure 46.

Coaxially disposed within the inner ceramic insulator sleeve 142 is inner pin contact structure 150 which is generally in the form of a sleeve with a solid central portion 151. The inner pin contact structure 150 includes a generally tubular forward contacting portion 152 having a plurality of longitudinal slits 154 to provide a plurality of elongated contact fingers 156 which are arcuate or arched in cross-section and preferably are cornposed of spring metal. To the rear of the solid central portion 151 of inner pin contact structure 150 is an enlarged rearward cylindrical portion 158 of structure 150, portion 158 terminating at its rearward end in a terminal tab 160 which projects rearwardly into the cavity of end bell 110 and which has the other conductor wire 114 secured thereto as by brazing or welding.

The inner ceramic insulator sleeve 142 is undercut proximate its rear end to receive an annular braze 162 which secures the inner insulator sleeve 142 and the inner pin contact structure 150 to each other in sealed relationship proximate their rear ends.

A11 annular clearance 164 is provided between the reduced diameter forward contacting portion 15-2 of inner pin contact structure 150 and the inner cylindrical Wall of inner ceramic insulator sleeve 142 to receive the outer contact sleeve portion 74 of the central socket contact structure 72, the inner contact rod 76 of socket contact structure 72 penetrating the inside of the forward contacting portion 152 of inner pin contact structure 150.

It will be noted that as with the receptacle connector member 12, the brazes which are applied in the plug connector member 14 to secure the mounting sleeve 122, ceramic insulator sleeves 124 and 142, and pin contact structures 130 and 150 in their operative posi-y tions are longitudinally staggered, and this coupled with suitable yannular clearances between the various parts provides a bellows type of construction capable of maintaining an effective hermetic seal under widely varying temperature conditions despi-te differences in the coefficients of thermal expansion for the various coaxially arranged parts.

Referring now particularly to FIGURES l, 2 and 3 of the drawings, these figures illustrate the manner in which the plug end receptacle connector members and their respective contact structures mate. Interengagement of the connector members is effected by introducing the plug shell 92 into the receptacle shell 16 with receptacle polarizing key 22 oriented so as to slide within the polarizing slot 96 of the plug shell. Polarizing key 22 and slot 96 prevent relative rotation and corresponding damage to the mating contact structures as the plug end receptacle members are drawn together. The rotatable coupling sleeve 98 on the plug is threadedly engaged with the external threads on receptacle shell 16 and is rotated so as to draw the plug end receptacle members together. Mating of the respective contact structures is effected while the plug and receptacle members are thus being drawn together.

The forward contacting portion 132 of outer pin contact structure 130 slides through the inwardly projecting annular rib 54 which is part of the outer socket contact structure 46 and is picked up by -the entrance ramp 56 on the inner contact sleeve portion 50 of the outer socket contact structure 46. The contacting fingers 136 of the outer pin contact structure 130 are deliected outwardly along the entrance ramp 56 until they engage the outer contact sleeve portion 48 of outer socket contact structure 46 which again deliects the contacting fingers 136 into `a longitudinal direction, and the contacting fingers 136 are then fed into the annular space 52 between the outer and inner contact sleeves of the outer socket contact structure 46. The inwardly projecting rib 54 on the outer socket contact structure 46 insures a relatively abrupt outwardly deection of the contacting fingers 136 by the entrance ramp 56 of the outer socket contact structure 46, and the closely confining annular space 52 in the outer socket contact structure 46 insuresv a relatively abrupt deflection back to the axial direction.

Accordingly, the substantial forces involved which are required to apply these 4two bends to the pin contacting fingers 136 develop excellent contacting force between the mating contact members and also result in a good wiping action therebetween to free the engaging surfaces of oxides or other surface impediments to good electrical conduction between the mating contact members.

In addition to this double bend and corresponding serpentine movement and final configura-tion of the contacting fingers 136, the arcuate or arched cross-sectional shape of the contacting fingers 136 cooperates with this longitudinal double bending to further increase the effectiveness of the engagement between the mating contact members. This arcuate cross-section of the contacting lingers 136 has several important functions. For one thing, this cross-sectional shape provides excellent longitudinal rigidity to the cont-acting fingers 136 which causes a substantial increase in the forces required to apply the two longitudinal bends, thus increasing the contacting force and also limproving the wiping action. This increased longitudinal rigidity is accomplished by the arcuate cross-sectional shape without requiring any thickening of the metal of the contacting fingers 136, and relatively broad contacting surface areas with minimum space occupancy are accordingly provided.

Another important function of the arcuate cross-sectional shape of the contacting fingers 136 is best illustrated in FIGURE 3, where it is seen that the arched fingers are transversely compressed between the outer and inner contact sleeve portions of the outer socket contact structure 46 in such a manner as to provide three areas of pressurized contacting engagement for each of the contacting fingers 136. Thus, independent of the contacting force provided by the two longitudinal bends applied to the contacting fingers 136, the arcuate crosssectional shape of the contacting fingers provides additional transverse contacting pressure. This transverse interference fit of the contacting fingers 136 in the annular space 52 of the socket contacting structure 46 is accomplished in cooperation with the application of the double serpentine bending of the contacting fingers longitudinally because the contacting fingers are bent outwardly and then longitudinally to a final position which is substantially radially outwardly offset from the initial closed tubular configuration of the forward contacting portion 132 of the outer pin contact structure 130. Ac-

cordingly, the radius of curvature cross-sectionally of each of the contacting fingers 136 is substantially less -than the radius of curvature of the annular space 52 of the outer socket contact structure 46 within which the contact fingers 136 are forced.

This compound defiection of the contacting fingers 136 with two longitudinal bends and also lateral defiection provides excellent contacting force and wiping action even in a situation where the connector is subjected to such high temperatures that the spring characteristics which are preferably embodied in contacting fingers 136 are diminished or substantially destroyed.

The manner in which the inner pin contact structure 150 mates with the central socket contact structure 72 is similar to that described hereinabove for the outer pin and socket contact structures and 46, respectively. Thus, as best seen in FIGURE 2, as the plug and receptacle connector members are dravm together, the tubular forward contacting portion 152 of the inner pin contacting structure passes through the inwardly projecting rib 80 of the central socket contacting structure 72, and the contacting fingers 156 of the tubular forwardly contacting 'portion 152 are deflected outwardly by the entrance ramp or bevel 82 at the forward end of inner socket contact rod 76, the contacting fingers 156 being fed into the'confined annular space 78 between sleeve and rod portions 74 and 76, respectively, of socket contact structure 72 and being bent back into an axial direction therein. In addition to this double longitudinal bending of the contacting fingers 156, they are compressed and somewhat flattened laterally by virtue of their smaller transverse radius of curvature than that of the annular space 78 into which they are engaged.

Accordingly, it will be seen that the mating inner pin contact structure 150 and central socket contact structure 72 have the same advantages as the mating outer pin and socket Contact structures 130 and 46, respectively.

Although the present invention is effective for general electrical connector applications, it will be seen that it has especial utility for high temperature use, in which case the best materials available for high temperature conditions should be selected for the various parts. The use of ceramic insulators and the brazed and welded connections and seals are also particularly useful for high temperature conditions, although it is to be understood that for general applications where excessively high temperatures are not expected to be encountered other connecting means such as soldering or crimping and other conventional insulation materials may be employed. Additionally, although the present invention has been shown and described as a hermetically sealed connector, it is to be understood that the invention is not limited to a sealed type of connector, and that the novel contact structures of the invention have general utility in the connector art.

While the instant invention has been shown and described herein in what is conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope of the invention, which is therefore not to be limited to the details disclosed herein, but is to be accorded the full scope of the claims.

Having described our invention what we claim as new and desire to secure by Letters Patent is:

1. An electrical connector which comprises a pair of interengageable connector members each having a front and a rear end, each of said connector members including a tubular metal shell, the forward portions of said shells comprising coupling means adapted to guide forward engaging portions of said members in axially aligned relationship into and out of engaged relationship, elongated socket contact structure supported in one of said connector members land having a rearward terminal portion and a forward contacting portion, said forward contacting portion having inner and outer coaxially arranged annular means defining a generally longitudinally extending, forwardly opening, annular socket clearance, and elongated pin contact structure supported in the other connector member and having a rearward terminal portion and a forward contacting portion, said forward contacting portion of the pin contact structure comprising tube means longitudinally split to form a plurality of forwardly extending contacting fingers, said tube means having a smaller diameter than said socket clearance, and entrance ramp means on at least one of said pin and socket contact structures, whereby as the connector members are moved into their engaged relationship said contacting fingers will be deflected outwardly by said entrance ramp means and slidably engaged within said socket clearance in an interference fit between said inner and outer annular means of the socket contact structure, a metal sleeve coaxially disposed within a rearward portion of each of said shells, a ceramic insulator sleeve coaxially disposed within each of said metal sleeves, said contact structure of each connector member having a tubular portion disposed rearwardly of the respective forward contacting portion and coaxially disposed within said ceramic insulator sleeve, fir'st annular sealing means between each shell and the respective said metal sleeve therein, second annular sealing means between each metal sleeve and the respective said ceramic insulator sleeve therein, and third annular sealing means between each ceramic insulator sleeve and said tubular portion of the respective contact structure therein, said second sealing means being axially spaced in one direction from said first sealing means and said third sealing means being axially spaced in the opposite direction from said second sealing means.

2. An electrical connector as defined in claim 1 wherein said second and third sealing means are metal-toceramic brazes.

3. An electrical connector as defined in claim 2 which includes an inner ceramic insulator member coaxially disposed within said tubular portion of the respective said contact structure, and a second one of said contact structures coaxially disposed within the first mentioned said contact structure of each connector member, said second contact structures each having a said tubular portion coaxially disposed within the respective inner ceramic insulator member, fourth `annular sealing means comprising a metal-to-ceramic ,braze between said tubular portion of each of the first mentioned contact structures and the respective said inner ceramic insulator member therein, and fifth annular sealing means comprising a metal-to-ceramic braze between each inner ceramic insulator member and said tubular portion of the respective said second contact structure therein, said fourth sealing means being axially spaced in said one direction from said third sealing means and said fifth sealing means being axially spaced in said opposite direction from said fourth sealing means.

4. An electrical connector member which comprises a tubular metal shell having front and rear ends, a forward portion of the shell being adapted for engagement with another connector member, a metal sleeve coaxially disposed within a rearward portion of said shell, an insulator sleeve coaxially disposed Within said metal sleeve, and electrical contact structure in said connector member, said contact structure having a rearward tubular portion coaxially disposed within said insulator sleeve and having a forward contacting portion adapted to mate with an opposed contact member of said other connector member, :first annular sealing means between said shell and said metal sleeve therein, second annular sealing means between said metal sleeve and said insulator sleeve therein, and third annular sealing means between said insulator sleeve and said tubular portion of the contact structure therein, said second sealing means being axially spaced in one direction from said first sealing means and said third sealing means being axially spaced from said second sealing means.

5. An electrical connector member as defined in claim 4 wherein said insulator sleeve is composed of ceramic material, and said second and third sealing means comprise metal-to-ceramic brazes.

6. An electrical connector as defined in claim 4 which includes an inner insulator sleeve coaxially disposed within said tubular portion of said contact structure, and a second contact struct-ure coaxially disposed Within the first mentioned said contact structure, said second contact structure having a tubular rearward portion coaxially disposed within said inner insulator sleeve, fourth annular sealing means between said tubular portion of the first mentioned contact structure and said insulator sleeve therein, and fifth annular sealing means between said inner insulator sleeve and said tubular portion of said second contact structure therein, said fourth sealing means being axially spaced in said one direction from said third sealing means and said fifth sealing means being axially spaced in said opposite direction from said fourth sealing means.

7. An electrical connector member as defined in claim 6 wherein said insulator sleeves are composed of ceramic material, and said second, third, -fourth and fifth sealing means comprise metal-to-ceramic brazes.

8. An electrical connector which comprises elongated socket contact structure having front and rear ends and including a forward contacting portion having a forwardly opening, elongated socket clearance which is arcuate in cross-section, said clearance being defined between a pair of opposed, elongated socket surfaces which are arranged in substantially parallel relationship, said opposed socket surfaces each being arcuate in cross-section, with one of them convex and the other concave, and elongated pin contact structure having front and rear ends and including forwardly extending, laterally deformable contacting finger means Which is arch-shaped in crosssection with arcuate concave and convex sides, said finger means being longitudinally slidably engageable in an interference fit within said socket clearance with said concave side of the finger means engaged against said convex socket surface and said convex side of the finger means engaged against said concave socket surface, the radius of curvature of each side of the finger means being materially smaller than that of the respective socket surface which it engages so that the interference fit of the finger means in the socket clearance causes a flattening deformation of the finger means.

9. An electrical connector as defined in claim 8, wherein said finger means is composed of spring material.

10. An electrical connector as defined in claim 8, wherein said socket clearance is annular and said socket surfaces are generally coaxial and circularly cylindrical, said finger means comprising a plurality olf discrete fingers arranged generally in a tubular array. l

11. An electrical connector which comprises a pair of interengageable connector members each having a front and a rear end, coupling means on said connector members adapted to guide forward enga-ging portions of said members in axial alignment into and out of the engaged relationship, elongated socket contact structure supported in one of said connector members and including a forward contacting portion having a forwardly opening, elongated socket clearance arranged generally parallel to the axis of the connector, said clearance being defined between a pair of opposed, elongated socket surfaces which are arranged in substantially parallel relationship, and'l elongated pin contact structure supported in the other connector member and including forwardly extending, longitudinaly deformable contacting finger means arranged generally parallel to the axis of the connector and laterally offset from said socket clearance prior to engagement of the finger means in the socket clearance, a substantial forward portion of the length of said finger means being longitudinally slidably engageable in said socket clearance in an interference t between said opposed socket surfaces, and entrance ramp means on at least one of said socket and pin contact structures for deflecting the forward end .of said finger means laterally in a first bend from said offset position into said socket clearance as the connector members are moved into their engaged relationship, confinement of the forward portion of thel finger means between said opposed socket surfaces as the connector members move further into engagement directing the confined portionr of the finger means into axial alignment with said socket clearance and thereby de-forming said finger means in a second bend directed oppositely to said first bend and located between said first bend and the entrance of said said socket clearance, said longitudinal engagement of said substantial forward portion of the length of said finger means causing said second bend to shift rearwardly along the finger means as the connector members are moved closer toward their fully engaged relationship.

12. An electrical connector as defined in claim 11, which includes rib means on said socket contact struct-ure spaced forwardly of the forward opening of said socket clearance and projecting laterally into the line of said socket clearance so as to require the finger means to bend over said rib means proximate said first bend, longitudinal movement of the finger means over said rib means during the engaging movement of the connector members causing said first bend to shift rearwardly along the finger means.

13. An electrical connector as defined in claim 11, wherein said elongated socket clearance is arcuate in crosssection, said opposed socket surfaces each being arcuate in cross-section with one of them convex and the other concave, and wherein said finger means is laterally deformable and arcuate in cross-section with arcuate concave and convex opposite sides, said concave sides of the finger means -being engaged against said convex socket surface and said convex side of the `finger means being engaged against said concave socket surface, the radius of curvature of each side of the finger means being materially smaller than that of the respective socket surface whichit engages so that the interference fit of the nger means in the socket clearance will cause a flattening deformation o-f the finger means.

14. An electrical connector as defined in claim 13, wherein said socket clearance is generally in the shape of a circular cylinder, and said forward contacting portion of the pin contact structure comprises longitudinally split tube means generally axially aligned with said socket clearance and having a smaller radius of curvature than that of said socket clearance.

15. An electrical connector as defined in claim 14, which includes a radially inwardly directed annular rib on said socket contact structure spaced forwardly of the forward opening Iof said socket clearance and projecting -radially inwardly into the line of said socket clearance so as to require the finger means to bend radially outwardly over said rib means proximate said first bend, longitudinal movement of the finger means over said rib during the engaging movement of the connector members causing said first bend to shift rearwardly along the finger means.

References Cited by the Examiner UNITED STATES PATENTS 1,258,304 3/1918 Bishop 339-276 X 1,769,325 7/ 1930 Warber 339-258 X 1,963,793 6/1934 Kimbell 339-258 X 2,225,461 12/1940 Reynolds 339-177 X 2,294,738 9/ 1942 Bruno 339-258 X 2,461,268 2/1949 Goldeld 339-177 X 2,771,295 11/1956 Andres 339-273 X 2,794,961 6/1957 Knight 339-273 X FOREIGN PATENTS 946,363 8/ 1956 Germany.

PATRICK A. CLIFFORD, Primary Examiner. W. D. MILLER, Assistant Examiner. 

1. AN ELECTRICAL CONNECTOR WHICH COMPRISES A PAIR OF INTERENGAGEABLE CONNECTOR MEMBERS EACH HAVING A FRONT AND A REAR END, EACH OF SAID CONNECTOR MEMBERS INCLUDING A TUBULAR METAL SHELL, THE FORWARD PORTIONS OF SAID SHELLS COMPRISING COUPLING MEANS ADAPTED TO GUIDE FORWARD ENGAGING PORTIONS OF SAID MEMBERS IN AXIALLY ALIGNED RELATIONSHIP INTO AND OUT OF ENGAGED RELATIONSHIP, ELONGATED SOCKET CONTACT STRUCTURE SUPPORTED IN ONE OF SAID CONNECTOR MEMBERS AND HAVING A REARWARD TERMINAL PORTION AND A FORWARD CONTACTING PORTION, SAID FORWARD CONTACTING PORTION HAVING INNER AND OUTER COAXIALLY ARRANGED ANNULAR MEANS DEFINING A GENERALLY LONGITUDINALLY EXTENDING, FORWARDLY OPENING, ANNULAR SOCKET CLEARANCE, AND ELONGATED PIN CONTACT STRUCTURE SUPPORTED IN THE OTHER CONNECTOR MEMBER AND HAVING A REARWARD TERMINAL PORTION AND A FORWARD CONTACTING PORTION, SAID FORWARD CONTACTING PORTION OF THE PIN CONTACT STRUCTURE COMPRISING TUBE MEANS LONGITUDINALLY SPLIT TO FORM A PLURALITY OF FORWARDLY EXTENDING CONTACTING FINGERS, SAID TUBE MEANS HAVING A SMALLER DIAMETER THAN SAID SOCKET CLEARANCE, AND ENTRANCE RAMP MEANS ON AT LEAST ONE OF SAID PIN AND SOCKET CONTACT STRUCTURES, WHEREBY AS THE CONNECTOR MEMBERS ARE MOVED INTO THEIR ENGAGED RELATIONSHIP SAID CONTACTING FINGERS WILL BE DEFLECTED OUTWARDLY BY SAID ENTRANCE RAMP MEANS AND SLIDABLY ENGAGED WITHIN SAID SOCKET CLEARANCE IN AN INTERFERENCE FIT BETWEEN SAID INNER AND OUTER ANNULAR MEANS OF THE SOCKET CONTACT STRUCTURE, A METAL SLEEVE COAXIALLY DISPOSED WITHIN A REARWARD PORTION OF EACH OF SAID SHELLS, A CERAMIC INSULATOR SLEEVE COAXIALLY DISPOSED WITHIN EACH OF SAID METAL SLEEVES, SAID CONTACT STRUCTURE OF EACH CONNECTOR MEMBER HAVING A TUBULAR PORTION DISPOSED REARWARDLY OF THE RESPECTIVE FORWARD CONTACTING PORTION AND COAXIALLY DISPOSED WITHIN SAID CERAMIC INSULATOR SLEEVE, FIRST ANNULAR SEALING MEANS BETWEEN EACH SHELL AND THE RESPECTIVE SAID METAL SLEEVE THEREIN, SECOND ANNULAR SEALING MEANS BETWEEN EACH CERAMIC INSULATOR RESPECTIVE SAID CERAMIC INSULATOR SLEEVE THEREIN, AND THIRD ANNULAR SEALING MEANS BETWEEN EACH CERAMIC INSULATOR SLEEVE AND SAID TUBULAR PORTION OF THE RESPECTIVE CONTACT STRUCTURE THEREIN, SAID SECOND SEALING MEANS BEING AXIALLY SPACED IN ONE DIRECTION FROM SAID FIRST SEALING MEANS AND SAID THIRD SEALING MEANS BEING AXIALLY SPACED IN THE OPPOSITE DIRECTION FROM SAID SECOND SEALING MEANS. 